laiyp/lib_xua
1
0
Fork 0
forked from PAWPAW-Mirror/lib_xua
Code Pull Requests Activity

Update I2S input buffering to support downsampling scheme

Browse Source 
Also:

- Replace defines added for I2S downsampling with existing defines.

- Remove downsampledI2S[] buffer until DS3 API is finalised.
  Samples from samplesIn[] are output instead for now.
This commit is contained in:
Sam Chesney
2016-11-30 10:12:26 +00:00
parent 020cf2dad7
commit dde838c940
1 changed files with 11 additions and 13 deletions
Download Patch File Download Diff File Expand all files Collapse all files

24
module_usb_audio/audio_io/audio_io.xc
View File

@@ -40,15 +40,14 @@
#error "Unsupported I2S rate scaling and downsampling configuration"
#endif
// I2S channels for stereo AEC reference input
#define I2S_CHANS_DIGI_IN (2)
// The PDM mic channels start after the I2S AEC reference channels
#define PDM_RX_INDEX (I2S_CHANS_DIGI_IN)
#if (NUM_USB_CHAN_IN < (I2S_CHANS_DIGI_IN + NUM_PDM_MICS))
#if (NUM_USB_CHAN_IN && (NUM_USB_CHAN_IN < (I2S_CHANS_ADC + NUM_PDM_MICS)))
#error "Not enough USB input channels to support number of I2S and PDM inputs"
#endif
#if (NUM_USB_CHAN_IN && (NUM_USB_CHAN_IN < (NUM_PDM_MICS + PDM_MIC_INDEX)))
#error "PDM mic inputs mapping exceeds bounds of USB input channel"
#endif
/* TODO 32 is max expected channels */
static unsigned samplesOut[32];
@@ -287,19 +286,18 @@ static inline unsigned DoSampleTransfer(chanend c_out, const int readBuffNo, con
inuint(c_out);
#endif
}
unsigned downsampledI2S[2];
// TODO: run ds3 here
// Pass samplesIn[readBuffNo][0,I2S_DOWNSAMPLE_FACTOR][i]) to ds3()
UserBufferManagement(samplesOut, samplesIn[readBuffNo][downsamplingCounter], i_audMan);
#if NUM_USB_CHAN_IN > 0
#pragma loop unroll
for(int i = 0; i < I2S_CHANS_DIGI_IN; i++)
for(int i = 0; i < I2S_CHANS_ADC; i++)
{
outuint(c_out, downsampledI2S[i]);
outuint(c_out, samplesIn[readBuffNo][downsamplingCounter][i]);
}
#pragma loop unroll
for (int i = PDM_RX_INDEX; i < (NUM_PDM_MICS + PDM_RX_INDEX); i++)
for (int i = PDM_MIC_INDEX; i < (NUM_PDM_MICS + PDM_MIC_INDEX); i++)
{
outuint(c_out, samplesIn[readBuffNo][downsamplingCounter][i]);
}
@@ -640,7 +638,7 @@ unsigned static deliver(chanend c_out, chanend ?c_spd_out,
asm volatile("in %0, res[%1]" : "=r"(sample) : "r"(p_i2s_adc[index++]));
/* Note the use of readBuffNo changes based on frameCount */
samplesIn[buffIndex][((frameCount-2)&(I2S_CHANS_PER_FRAME-1))+i] = bitrev(sample); // channels 0, 2, 4.. on each line.
samplesIn[buffIndex][downsamplingCounter][((frameCount-2)&(I2S_CHANS_PER_FRAME-1))+i] = bitrev(sample); // channels 0, 2, 4.. on each line.
}
#endif
@@ -721,7 +719,7 @@ unsigned static deliver(chanend c_out, chanend ?c_spd_out,
master
{
#pragma loop unroll
for(int i = PDM_RX_INDEX; i < (NUM_PDM_MICS + PDM_RX_INDEX); i++)
for(int i = PDM_MIC_INDEX; i < (NUM_PDM_MICS + PDM_MIC_INDEX); i++)
{
c_pdm_pcm :> samplesIn[readBuffNo][downsamplingCounter][i];
}
@@ -740,7 +738,7 @@ unsigned static deliver(chanend c_out, chanend ?c_spd_out,
unsigned sample;
asm volatile("in %0, res[%1]" : "=r"(sample) : "r"(p_i2s_adc[index++]));
samplesIn[buffIndex][((frameCount-1)&(I2S_CHANS_PER_FRAME-1))+i] = bitrev(sample); // channels 1, 3, 5.. on each line.
samplesIn[buffIndex][downsamplingCounter][((frameCount-1)&(I2S_CHANS_PER_FRAME-1))+i] = bitrev(sample); // channels 1, 3, 5.. on each line.
}
#endif